Gel electrophoresis is a technique that is commonly employed in molecular biology for determining the size distribution of restriction enzyme digests of DNA. This technique has found widespread use in research, as well as in practical applications. It has been found that certain DNA banding patterns detectable by electrophoresis are often associated with specific disease states. Thus, the electrophoretic analysis of samples obtained from a patient may allow physicians to make or confirm a particular diagnosis.
Other applications have resulted from the fact that DNA samples obtained from a particular individual can be digested with restriction enzymes, the fragments separated by electrophoresis and the resulting pattern of bands used to unambiguously identify that particular individual (except in the case of identical twins). Consequently, the electrophoretic analysis of DNA is finding application in the area of law enforcement. A person convicted of a crime may have a sample taken for DNA analysis. The results of this "DNA fingerprint" are compared to evidentiary material found at the scene of a crime or are kept on record and used for future comparison in much the same way as conventional fingerprints.
However, because the resulting data will be used in courts of law, the identification of individuals by DNA fingerprinting is technically demanding and must be done by laboratories with specialized equipment and personnel. This creates a problem of quality control. Specifically, when the electrophoretic positions of DNA bands is critical data and samples are being analyzed on an industrial scale (tens of thousands of samples per year) by independent testing laboratories, it is important to know whether the data reported can be relied upon, i.e., do the results reported accurately represent the banding pattern as it should appear if all of the steps in the analysis had been correctly performed. The present invention is specifically aimed at addressing this problem.